Which advantages does Unix have over Linux that it is still used by systems administrators? Will it become obsolete ultimately? Which OS have potential as a server OS with exception of Windows and Linux? What about Mac OS or Android? Is Novell's Netware practically obsolete?

1 hour ago, Moreno said:

What about Mac OS or Android?

Both of these are Unix derived (or Unix-like) operating systems. Mac OS is used in servers, to a limited extent.  

Linux is just an evolution of Unix. Both Linux and Windows are so well established in the corporate world that it it will be difficult for an external OS to come into play any time soon. Mac OS is not a server ioerating system and Android is purely for mobile devices so no as well. There are still uses in exotic environments fir pure Unix but its a niche. Linux and Windows rule and will rule for years to come. All the competition is long dead (Novell for example)

6 minutes ago, Strange said:

Both of these are Unix derived (or Unix-like) operating systems. Mac OS is used in servers, to a limited extent.  

To add macos is bsd and android uses the Linux kernel. 

Having done some work on (early versions of) Android, I do not have a very high opinion of the software produced by Google. It seems to be thrown together by a large number of different people with no overall plan. I don't know if that is just Android, but (based on my experience of a large number of different software teams) I see no reason to think that the rest of their software would be any better. 

13 hours ago, Strange said:

It seems to be thrown together by a large number of different people with no overall plan.

I would say so it's normal in corporate IT...

Developers come and go all the time..

 

Is Unix still more secure and reliable than Linux? What about speed anf functionality?

 

Which flavour of Linux is most commonly used by server administrators at least in US?

1 hour ago, Moreno said:

Which flavour of Linux is most commonly used by server administrators at least in US?

I’d say „Ubuntu” and „Suse” but there so many distributions and the whole scene evolves constantly.

12 hours ago, koti said:

I’d say „Ubuntu” and „Suse” but there so many distributions and the whole scene evolves constantly.

Interesting, I'd say Debian and rhel. 

In terms of devices, I wouldn't be surprised if raspbian was one of he most used now. 

On 13/10/2017 at 2:37 AM, Moreno said:

Is Unix still more secure and reliable than Linux? What about speed anf functionality?

 

That depends on which Unix, which Linux and your application. 

1 hour ago, Klaynos said:

Interesting, I'd say Debian and rhel. 

Yeah, Debian too. I was in a training for linux administrators rcently and it delt with Ubuntu so I might be biased.